Spider and silkworm produce animal silks exhibiting outstanding mechanical properties by using smart spinning method. In this paper, a biomimetic spinning of spider silk and silkworm silk was studied from various routes. Regenerated silk fibroin (RSF) aqueous solution was firstly dry-spun to artificial fiber in air at room temperature as the animal silks were made naturally. The conformation transition of the silk fibroin was then induced by post-drawing in ethanol aqueous solution. The oriented crystalline and amorphous regions of the silk fibers contribute to the remarkable mechanical properties of the artificial silk, which exceed those of natural silkworm silk. By mimicking the functions of the spinning apparatus of spider and silkworm, ion and protein concentrations in the RSF aqueous solution were adjusted in microfluidic chips with multiple channels. Inspired by the shape and dimensions of the natural spinning apparatus, a microfluidic chip was designed and applied to the studies of aggregation mechanism of silk fibroin in micro-channel. Moreover, the supermolecular structures of silk fibroin were effectively controlled to reinforce dry-spun/electrospun fibers of RSF by mimicking the core-shell structure of natural animal silks, adding silk sericin or carbon nanotube in spinning solutions and changing the collecting method in electrospinning process.

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The paper presents luminescence properties of platinum porphyrins embedded in ultrathin polymer Langmuir-Blodgett (LB) films (nanosheets). We prepared amphiphilic copolymer of platinum porphyrin with N-dodecylacrylamide (p(DDA/PtTPP)). The copolymer p(DDA/PtTPP) with 6mol% PtTPP content took a stable monolayer formation at the air-water interface. Luminescent p(DDA/PtTPP) nanosheets were successfully assembled on solid substrates by the vertical dipping method. The luminescence intensity as a function of the number of layers revealed that platinum-porphyrin is effectively quenched by molecular oxygen for multilayered p(DDA/PtTPP) nanosheets with more than ten layers. Atomic force microscopy revealed that the p(DDA/PtTPP) nanosheets had relatively rough surfaces, leading to high surface-tovolume ratio. The oxygen sensitive polymer nanosheet multilayers enables us to monitor dissolved oxygen concentration in water.

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Self compacting concrete (SCC) is a material which 'poured' into the formwork compacts 'without any further compaction' and exhibits excellent flow behavior. De Schutter published a comprehensive overview on the state of the art of self compacting concrete where he presents the development from an early patent in Germany to the development of an industrially usable product in Japan. Meanwhile in the US the technology is referred to as "the New Normal" – meaning that SCC is going to be used as the normal way to produce concrete either in pre- fabrication or on site.
Part of this "New Normal" is a classification of SCC – which by the way might differ in different parts of the world-according to composition and properties of the fresh and hardened concrete. Amongst this classification in many countries a trend to "green" or sustainable SCC is observed and described. It consists of the challenge to maintain the excellent properties of the fresh and hardened concrete whilst optimizing the use of raw materials in such ways that
➣SCC production and use is associated with less energy and emissions
➣The CO₂ footprint is minimized
➣More secondary cementitious materials are used
The paper describes the state of the art of Self Compacting Concrete and the challenges to combine the above mentioned features with the traditional mix design of SCC as well as the impact this trend might have on development of SCC in the near future.

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This paper reviews some of the recent challenges in the sustainable processing of primary mineral resources and discusses the technical prospects for meeting these challenges. The second part describes the integrated approach of geometallurgy being a prerequisite for improving resource efficiency along the production chain of minerals and metals. The different elements of a geometallurgical program are discussed and examples for ongoing geometallurgical research and education as pursued at Luleå University of Technology are presented.

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The results of studies of the magnetic properties of thin films and multilayer structures based on FeM (where M = Cо, Pt) obtained using ⁵⁷Fe Mössbauer spectroscopy. It is shown that Mössbauer spectroscopy is a valuable method for the study of thin films and multilayer systems.

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The method for the recovery of gold from its flotation concentrate using acidic thiourea leaching followed by adsorption on an organosilicon polymer (PSTM-3C) was discussed in the present study. The study had allowed identification of the effect of thiourea, oxidizer and acid concentration, leaching time, temperature and pulp density on gold dissolution in thiourea solution. The results showed that the vast majority of gold (93.6%) from the gold concentrate was dissolved in nitric acid solution with thiourea under the optimum conditions. Whereas some accompanying elements like Se, Te, V, Cr and Ni in the concentrate were insoluble in the acidic thiourea solution. Gold was recovered from the leach liquor by adsorption on the organosilicon polymer PSTM-3C. The influence of acid concentration, adsorption time and temperature was studied for gold recovery using the polymer. The result showed that about 94.4% of gold was adsorbed on the polymer from the liquor after the optimization of the experimental conditions. The FT-IR anaylsis revealed that when the polymer adsorbed Au from the liquors, a new IR band appeared at 1703 cm^-1 while the IR band at 1554.5 cm^-1 which observed in the IR spectrum of the pure polymer was disappeared.

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In the past two decades or so, titanium and its alloys have found a significant increase in the aerospace applications. One of the reasons is associated with the introduction of various new titanium alloys. Ti-5Al5V-5Mo-3Cr (Ti5553) is one of the most notable new titanium alloys. This alloy has a high strength, excellent hardenability and good fracture toughness. Landing gear beam truck of aircraft has been successfully manufactured using this alloy. In order to find more applications in various areas, a number of factors are to be investigated, and one of them is its weldability. Three types of welding methods were used in this investigation, i.e. Laser Beam Welding (LBW), Electron Beam Welding and Gas Tungsten Arc Welding (GTAW). The results showed that it is possible to perform similar Ti5553 alloy weld as well as dissimilar titanium welds. It was observed that the (i) strength at the weld zones was lower compared with the base metal, and (ii) grains grew epitaxially from the near heat affected zone into the fusion zones. This study is part of a strong on-going collaboration projects between Akita University and Auckland University of Technology.

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A new two-step process, chlorination reduction of molten fly ash with waste plastics (PVC) to separate harmful substances, such as Na, K, Cl, Zn and Pb, from the ash, and transformation from the ash into functional materials by hydrothermal treatment with sodium hydroxide, was attempted. The ash was mixed with PVC (1:1), and then the mixture was heated at 1000℃ in nitrogen gas. After heating, the residue was heated again at 1000℃ in air to obtain the treated ash. Although raw ash contains harmful substances such as Na, K, Cl, Zn and Pb, treated ash has lower contents of these substances than raw ash. Mineral phases in treated ash are mainly gehlenite, due to the disappearance of sodium chloride and potassium chloride in raw ash by two-step treatment with PVC. While a large amount of harmful ions, (Na^＋, K^＋, Cl^－, Zn^2＋ and Pb^2＋) were eluted, the elution of Na^＋ and K^＋ from treated ash was not observed, and those of Cl^－, Zn^2＋ and Pb^2＋ decreased. Raw ash or treated ash was treated with 2 M NaOH solution at 180℃ for 20 h to obtain functional materials. From both ashes, tobermorite 11 Å and hydroxyapatite can be synthesized.

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Sodium hydride in polyethylene glycol has been used as a sustainable, non-volatile, and ecofriendly catalytic medium for the green synthesis of bisphosphonates with an alkyl/aryl/heterocyclic group fixed at the geminal carbon. All compounds (3a-j) were characterized by IR, ¹H and ³¹P NMR, mass and elemental analysis. The easy recyclability of the reaction medium makes the reaction economically and potentially viable for commercial applications.

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For the selective electro-preparative syntheses of organic compounds, the electrode system composed of a graphite felt (GF) electrode coated with mediator-modified poly(acrylic acid) (PAA) was designed and prepared. In this study, characteristics of three GF electrodes differing from raw materials and the surface characteristics of these GF electrodes immobilizing redox mediator of 2,2,6,6-tetra- methylpiperidinyl-1-oxyl (TEMPO) were discussed. Among TEMPO-modified PAA-coated GF electrodes tested, the GF electrodes originated from pitch fibers was the best results for the enantio- and stereo-selective oxidations of geraniol and 2-naphthol, respectively, than the GF electrodes originated from polyacrylonitrile and phenolic resin fibers. The oxidation of racemic sec-alcohols and diols by chiral TEMPO of (6S, 7R, 10R)-4-amino-2,2,7- trimethyl-10-isopropyl-1-azaspiro[5,5]undecane-N-oxyl were carried out in high enantio- and stereo-selective yield and high isolated yield, respectively. The system can provide an ecologically clean process and will contribute to the development of green chemistry.

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Digital cameras as well as smart phones, tablet terminals, and mobile phones with built-in cameras are popular today because of their ease of use. The ubiquity of mobile camera phones, in particular, has allowed widespread use of quick-response (QR) codes for delivering information services. For this purpose, it is important for image processors to be able to identify a signboard in an image and extract its character sequences. Techniques for extracting a character sequence from a signboard can be combined with various other systems to realize a range of services. In a previous study, we proposed a method for detecting a character sequence from images captured in the daytime. To construct an effective recognition system, it is also important to examine images captured at night. At night, electric signboards are more clearly visible, but it is still necessary to consider conditions that may affect electric signboards, such as stains or lighting irregularities. Therefore, we propose a method for extracting a character sequence from an electric signboard in nighttime scene images.

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Facial expression recognition for emotional communication between humans and machines has been investigated in recent studies. Previously, we proposed a method for generating a person-specific emotional feature space using self-organizing maps and counter propagation networks (CPN). The feature space expresses the correspondence between the changes in facial expression patterns and the degree of emotions in a two-dimensional space centered on "pleasantness" and "arousal." In this study, we investigated the number of dimensions and the size of the CPN mapping space for generating a facial expression feature space that allows detailed emotion quantification.

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Structure–property relations for isomeric aromatic polyimides containing asymmetric aromatic imide structures have been discussed. Asymmetric polyimide 2,3,3’,4’-oxyphthalic dianhydride(a-ODPA) with 4,4’-oxydianiline(4,4’-ODA) exhibited higher Tgs than those of symmetric s-ODPA/4,4’ODA. Furthermore, the polyimide indicated a large drop in the storage modulus, E’ beyond the Tg. Based on these results, novel asymmetric polyimide (ISAS-TPI) was developed for heat sealable polyimide film with high stability in space. This paper also presents an application of the thin ISAS-TPI film: the world’s first solar sail membrane, used for “IKAROS”

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Polymeric resins with different copolymeric matrices viz., acrylonitrile/divinylbenzene/vinylbenzyl chloride (AN/DVB/VBC), styrene/divinylbenzene/vinylbenzyl chloride (ST/DVB/VBC), vinylbenzyl chloride/divinylbenzene (VBC/DVB) have been prepared by suspension polymerization. The polymeric matrices were functionalized with ethylenediamine (ED) and were employed as sorbents for the removal of copper ions from aqueous solution by the batch sorption method. Synthesized resins were characterized using FTIR, elemental analysis, DSC, BET surface area and SEM with EDAX analysis. The influences of pH, effect of contact time, interfering of common ions, selectivity of other metal ions and temperature on the amount of copper sorption by the modified resins were studied. AN/DVB/VBC-ED resin was found to have excellent copper sorption capacity (CSC) than the other prepared resins. The experimental data fitted well to the Langmuir and Freundlich isotherms. Thermodynamic parameters such as ΔH°, ΔS° and ΔG° were calculated indicating that the sorption was a spontaneous and endothermic. The removal of copper by the resins was mainly governed by chelation mechanism. AN/DVB/VBC-ED resin was effectively regenerated using 0.1 M EDTA and reused for more than 5 cycles.

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To overcome the strong van der Waals interactions of carbon nanotubes (CNTs) that hinder them from dissolving and dispersing in solvents, organic molecules used as dispersants are attached to the CNT surface by noncovalent interactions. In this study, polysulfones were selected as the dispersants, and the relationship between polymer structure and CNT dispersibility was investigated. We prepared nine types of polysulfones to study the dispersibility of multi-walled CNTs (MWCNTs). Polysulfones having sulfide bonds exhibited the highest MWCNT dispersibility. This result is due to the existence of donor–acceptor interactions between sulfide groups and MWCNTs, along with π–π interactions between aromatic rings and MWCNTs. The MWCNT solution in N,N-dimethylacetamide, dispersed by polysulfones, could be used for the preparation of MWCNT-containing films. The resulting films showed higher tensile strength and modulus than those of corresponding non-MWCNT-containing films. This result clearly indicates that MWCNT-dispersed solution using polysulfones can be used to prepare CNT/polymer composites.

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Currently, feasibility studies of seawater flotation for copper recovery from ores have been carried out in the mineral processing field. In this study, we investigated the influence of seawater on behavior of particle and bubbles of the copper flotation. Samples of crude copper sulfide ore mainly containing chalcopyrite(CuFeS₂), magnetite (Fe₃O₄) and quartz (SiO₂) were used in this study. The results showed that copper recovery by flotation with methyl iso butyl carbinol (MIBC) in distilled water and seawater reached 97% and 86%, respectively. It was observed that when DOW froth 250 was used as a frother in flotation in distilled water, copper (Cu) recovery didn’t change obviously, whereas the copper recovery increased up to 97% in flotation in seawater. It can be seen that diameter of bubbles in the seawater was increased when use the frother (DOW froth 250) in the flotation. The froth layer generated from the flotation in seawater is thicker than that flotation in distilled water. The thickness of froth layer which may be the reason why the copper recovery was higher in seawater flotation.

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Tamagawa hot spring water (Akita, Japan) is naturally acidic (pH 1.2) and concentration of rare earth elements (REEs) were found to be very low (1-70 µg/L). In this study, an effective enrichment for recovery of the REEs from the acidic hot spring water using adsorption and precipitation methods was investigated.Three polymers, namely Strata-X-C, TE-07 and TE-08 were used for adsorption of REEs from hot spring water, and adsorption and desorption of the REEs were carried out using a column type reactor. A strong cation exchange polymer (Strata-X-C, Phenomenex) was found to have very high adsorption of REEs. It was found that over 99% of REEs were adsorbed by Strata X-C within 1 min when the flow rate of hot spring water was 1 mL/min. Hydrochloric acid (6M-HCl) was used for desorption of REEs from polymeric resins, and results revealed that 70% of REEs could be recovered from the adsorbent by desorption. For further enrichment of REEs from the concentrated solution, NaOH was added in the solution to generate REEs as hydroxide precipitate. Concequently, the precipitate found to contain 1,100 g/t of REEs and we could enrich the over 5,700 times higher concentration of REEs compared to original Tamagawa hot spring water.

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Extraction reagents based on p-t-octylcalix[4]arene with ketonic and 2-pyridyl groups were prepared to investigate extraction behavior of precious metal ions by using microreactor system. Although the ketonic derivative exhibited high silver selectivity in nitric acid media, it took for more than 72 h to reach extraction equilibrium. On the contrary, the extraction rate was drastically improved by using microreactor system. It took for 16 s to extract silver ion by using parallel two phases flow type microreactor. The silver extraction rate was further improved by using slug flow type microreactor to be within 4 s. The extraction rate for ketonic derivative was much more improved compared with that for 2-pyridyl one. One of the reasons why silver extraction rate was drastically improved by using microreactor system was attributed to the enhanced interfacial area. It was supported by the result for the interfacial tension measurement of two extraction reagents.

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When two different colors are alternately displayed at a high speed, a mixed color is perceived. When two images of different colors are alternately displayed on a Liquid Crystal Display (LCD), a deterrent effect on copy is expected because the color of the copied image is different from that of the perceived image. It is also expected that display color increases without improvement to the LCD. However, flicker may occur in the LCD. The purpose of this study was to clarify the conditions for flickerless alternating display. We focused on subpixels constituting pixels on the LCD, and carried out three experiments. First, we examined whether flicker was felt when the light of the subpixel was blinking, and clarified the luminance range within which flickerless blinking is possible. Second, the presence or absence of flicker was examined when two colors with the same luminance were alternately displayed. Then, the range of luminance change in subpixels in an alternating display was compared with the luminance range clarified in the first step. Third, the presence or absence of flicker and the range of luminance change on subpixels were also investigated when achromatic colors were alternately displayed. The experimental results showed that the luminance change in each subpixel was related to the occurrence of flicker.

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Two kinds of new thiacalix[6]arene (TC6A) derivatives, TC6A-CH₂COOH (1) and TC6A-CSN(CH₃)₂ (2), were synthesized through modify at the lower rims of TC6A. The extraction of 1 or 2 for rare metal ions from platinum-group metals (PGM) solution containing eight rare metals (Rh, Pd, Pt, Zr, Ce, Ba, La, Y) and one base metal (Al) were investigated. Compound 1 showed selective extractability for Pd and Zr ions, which the extraction rates were 70% and 91%, respectively. The extraction rates of the other metal ions were below 5% by using 1 and 2. Compound 1 also showed stripping extraction ability of Pd ion by 7N HCl where the stripping ratio was ca. 70%. On the other hand, compound 2 indicated high selectivity of almost 100% Pd ion extraction from PGM solution.

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Effects of HNO₃ and H₃PO₄ on ion exchange of natural zeolite in a new-simple process, which is a twostep process using calcined hydrotalcite and natural zeolite, for making agricultural cultivation solution were examined. The anion-reduced solution obtained by the treatment of seawater with calcined hydrotalcite (CHT-solution) was neutralized with phosphoric (CHT-solution-H₃PO₄) or nitric acids (CHT-solutionHNO₃), and each four solutions (seawater, CHT-solution, CHT-solution-H₃PO₄ and CHT-solution-HNO₃) was treated with natural zeolite to compare the ion exchange behaviors among these solutions. The pH of the all solutions can be neutralized to 5.5 by zeolite treatment, and the Na⁺ content can be removed from the all solution. The tendencies of Na⁺ removal in all solutions are almost same, and percentages of Na⁺ removal from all solutions are above 95% over 8 times zeolite treatment. The amounts of supplies for K⁺, Mg²⁺ and Ca²⁺ to the CHT-solution-HNO₃ is higher than those of other solutions up to 6 times treatment. While almost PO₄^3- was removed, NO₃^- was remained in the solution, over 6 times treatment with natural zeolite. Therefore, NO^3- is possible to be supplied to the solution as nutrient in the two-step process, but PO₄^3- isn't possible.

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